The present invention relates to a welding apparatus of the type used in the entry section of a continuous processing line of strip steel for joining the ends of coils of strip steel, and more particularly the invention relates to an automatic edge aligning arrangement which is designed for use in combination with such welding machine.
Continuous processing lines of strip steel such as continuous mill lines or continuous annealing lines are conventionally operated in such a manner that the steel strip is rapidly fed to the line by one of a plurality of payoff reel units arranged in the entry section of the line to store the strip in the looper on the line, while on the other hand any off-gauge portion in the leading end of another coil steel fed by the following payoff reel unit is cut away and prepared for joining, so that as soon as the trailing end of the said proceeding coil is uncoiled, any off-gauge portion in the trailing end is cut away and the two ends are joined by welding to provide continuous section of the strip steel to the main processing section of the line, thus preventing the occurrence of stopping of the operation of the line.
A disadvantage of the above arrangement is that in the case of a line such as a high speed continuous annealing line for sheet-gauge coil stocks where the storage time of the entry-end looper is not sufficient and the line to which coils are to be fed requires a high degree of accuracy for the edge alignment of the coil ends, it has been the practice to manually accomplish the required edge alignment of the coil ends of strip steel with the resulting difficulty in obtaining the necessary operators and tendency to increase the down time of the entry section of the line.